bkahler Posted February 14, 2007 Report Posted February 14, 2007 I'm ready to bolt the road draft tube in place on my 218 and noticed that the fit is less than snug when sliding the tube into the block. It does appear that when sinched up the tube flange will be tight against the block. Does this seem correct? Thanks! Brad Quote
norrism1 Posted February 14, 2007 Report Posted February 14, 2007 It is open to the air anyway so no gasket is needed! Just tighten with a split washer if I remember correctly. Quote
grey beard Posted February 15, 2007 Report Posted February 15, 2007 Sorry bout 'dat, guys, but it's gotta be tight. It works by pulling a small vacuum on the bottom as you drive at road speed - well, at least it's supposed to work that way. If you really want a crankcase vent that works, go to VPW and buy a PCV adaptor that fits where the old road draft tube now sits. It'll keep your engine much cleaner inside, especially if you have a hing enough thermostat in the engine. JMHO Quote
Zeke1953 Posted February 15, 2007 Report Posted February 15, 2007 When I removed my down draft tube there was a thin, hard gasket between the tube and the engine block. It broke while taking it off, so I put a bead of RTV sealant on the tube before I reinstalled it. From what I've read, grey beard is right; the shape of the bottom of the tube and its location create a draft when the truck is moving that pulls the gases out of the block. This is why you also need to keep the screen in the oil filler cap clean so the air can flow through. Zeke Quote
bkahler Posted February 15, 2007 Author Report Posted February 15, 2007 When I removed my down draft tube there was a thin, hard gasket between the tube and the engine block. It broke while taking it off, so I put a bead of RTV sealant on the tube before I reinstalled it. From what I've read, grey beard is right; the shape of the bottom of the tube and its location create a draft when the truck is moving that pulls the gases out of the block. This is why you also need to keep the screen in the oil filler cap clean so the air can flow through. Zeke Ok, the little gasket makes sense. I'll have to dig up my engine gasket kit and see if there is something in there that will fit. If this was going to be a daily driver I might consider the pcv system but for now, or at least for a while I'll stick with the draft tube. Thanks for the replies! Brad Quote
Jim Dohr Posted February 15, 2007 Report Posted February 15, 2007 Does the draft tube cause a strong gasoline odor? Put my truck in the garage and its got a pretty strong petroleum smell. No leaks from the tank or filler neck. Any ideas? Quote
Robert Thornton Posted February 16, 2007 Report Posted February 16, 2007 You know i noticed my truck has a strong gas smell when in side also. I have the fuel tank out for work. this is the only time it does not have the oder. could it be venting through gas cap or bad seal on gas sending unit. i dont see any other way tank could vent. never any psi when removing gas cap. Quote
grey beard Posted February 16, 2007 Report Posted February 16, 2007 Your gas cap must have a vent built into it - otherwise the tank would pull a vacuum when the engine uses gas. If you smell gas in the garage and the bottom of the fuel tank is dry, helieve I would look at the fuel lines from the tank forward for any damp sopts. Also, you might remove the air cleaner while the engine is warm, and look for any dampness at the carburetor/fuel pump areeas. When a warm engine is shut off, much of the block and manifold heat rise. The carburetor and fuel line are sitting right on top of all that warm stuff, and the tendendy is for the fuel that is trapped in the line between the fuel pump and the carburetor neetle valve to expand, and force the float down, allowing extra fuel into the float bowl. Sometimes the bowl even runs over, just from the heat and the expanding fuel. This has often been a problem on more modern vehicles. It is called "hot soak" and can be remedied in a number of ways - often involving a new or modified needle and seat in the float chamber of the carburetor. Road draft tubes are just vents into the crankcase and valve cover areas. They will vent crankcase fumes and moisure, but not gasoline - unless your fuel pump is bad and is putting gas into the oil, in which case the oill on your dip stick would also smell of gasoline - not a difficult test for anyone to make. JMHO:) Quote
Robert Thornton Posted February 17, 2007 Report Posted February 17, 2007 Thanks Mr gray beard very good information. Quote
DanOlson Posted December 1, 2008 Report Posted December 1, 2008 Sorry bout 'dat, guys, but it's gotta be tight. It works by pulling a small vacuum on the bottom as you drive at road speed - well, at least it's supposed to work that way. If you really want a crankcase vent that works, go to VPW and buy a PCV adaptor that fits where the old road draft tube now sits. It'll keep your engine much cleaner inside, especially if you have a hing enough thermostat in the engine. JMHO What is VPW? Dan Quote
49plymouthdotcom Posted December 1, 2008 Report Posted December 1, 2008 What is VPW?Dan http://www.vintagepowerwagons.com/ Quote
lscrymgeour Posted December 1, 2008 Report Posted December 1, 2008 I had a gasoline smell in the cab when the truck was parked and even when driving slow. Solved it by properly positioning the rubber hose which joins the filler neck to the tank so that both parts are equally covered and replacing the wire clamps, which were flimsy, with hose clamps which are well tightened. Smell has gone even when parked inside. Lyle Quote
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